The coil tube bundle of Coil-wound heat exchanger (CWHE) is densely arranged, resulting in a complex flow domain in the shell. And Flow-induced vibration (FIV) is a common phenomenon in working situations where coil tubes are submerged in the oncoming flow. Understanding the flow and FIV characteristics of the shell-side plays a significant key in engineering issues, such as the design of coil tube bundle arrangements and safety verification of heat exchangers. This paper presented a detailed investigation of flow in the shell-side of the three-layer coil tube bundle with Detached eddy simulation (DES), whose validity was verified by comparison with the experimental results. Eight calculated cases of inlet flow rates from 0.01 m³/s to 0.15 m³/s with an interval of 0.02 m³/s were set up to determine that the flow domain of the shell-side is turbulent. The flow was found to form flow channels between adjacent layers, while variable eddy currents appeared around coil tubes. Subsequently, the gap transverse flow velocity was predicted and the calculation correlation was proposed. Furthermore, spectral and wavelet analyses were carried out to investigate the time-frequency data of fluctuating velocities in the flow, to bring to light vortex shedding frequencies and to capture St with respect to this tube bundle arrangement.

盘管式换热器（CWHE）的盘管束排列密集，导致壳内流域复杂。而流致振动（FIV）是盘管浸没在迎面而来的水流中的工作环境中的常见现象。了解壳程的流动和 FIV 特性在工程问题中起着重要的关键作用，例如盘管束布置的设计和热交换器的安全验证。本文采用分离涡模拟（DES）对三层盘管束壳程流动进行了详细研究，并通过与实验结果的比较验证了其有效性。^{0.01 m 3} /s 到 0.15 m ³ /s 间隔 0.02 m ³的入口流速 8 个计算案例/s 被设置来确定壳侧的流动域是湍流的。发现流动在相邻层之间形成流动通道，而在盘管周围出现可变涡流。随后，对间隙横向流速进行了预测，并提出了计算关系式。此外，进行了光谱和小波分析，以研究流动中波动速度的时频数据，揭示涡旋脱落频率并捕获与该管束排列相关的St。